Rich Internet Application

A rich Internet application (RIA; sometimes called an Installable Internet Application) is a Web application that has many of the characteristics of desktop application software, typically delivered by way of a site-specific browser, a browser plug-in, an independent sandbox, extensive use of JavaScript, or a virtual machine.Adobe Flash, JavaFX, and Microsoft Silverlight are currently the three most common platforms.

Google trends shows (as of September 2012) that frameworks based on a plug-in are in the process of being replaced by HTML5/JavaScript-based alternatives.

Users generally need to install a software framework using the computer's operating system before launching the application, which typically downloads, updates, verifies and executes the RIA. This is the main differentiator from HTML5/JavaScript-based alternatives like Ajax that use built-in browser functionality to implement comparable interfaces. As can be seen on the List of rich Internet application frameworks which includes even server-side frameworks, while some consider such interfaces to be RIAs, some consider them competitors to RIAs; and others, including Gartner, treat them as similar but separate technologies.

RIAs dominate in browser based gaming as well as applications that require access to video capture (with the notable exception of Gmail, which uses its own task-specific browser plug-in).Web standards such as HTML5 have developed and the compliance of Web browsers with those standards has improved somewhat.

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Wikipedia